The memory-placement rules are as follows:
The base machine contains one memory riser card with eight DIMM sockets. Memory
features occupy two memory DIMM sockets.
One additional memory riser card feature (1 x #5604) with an additional eight DIMM
sockets is available when one processor module is installed in the system. For the
Power 740, three optional memory riser card features (3 x #5604) with an additional eight
DIMM sockets per feature are available when two processor modules are installed in the
system.
A system can be ordered with a single memory feature #4526. When adding additional
memory to a system with 1 x #4526, a second 1 x #4526 must be ordered, and then all
memory must be ordered in increments of 2 x #4526.
A system cannot be ordered with a single memory feature #4529. All #4529 memory must
be ordered in quantity of 2 x feature #4529.
Feature #4526 and feature #4529 are allowed on the same memory riser card as long as
memory DIMMs are installed in quads (2 x #4526 or 2 x #4529).